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Mitochondria, oxidants, and aging.

Robert S Balaban1, Shino Nemoto, Toren Finkel

  • 1Laboratory of Cardiac Energetics, National Institutes of Health, Bethesda, Maryland 20892, USA.

Cell
|March 1, 2005
PubMed
Summary
This summary is machine-generated.

The free radical theory of aging suggests reactive oxygen species determine lifespan. This review examines evidence supporting and refuting this, linking mitochondrial metabolism and aging.

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Area of Science:

  • Gerontology
  • Cell Biology
  • Biochemistry

Background:

  • The free radical theory of aging, proposed over 50 years ago, posits that intracellular reactive oxygen species production is a key factor influencing lifespan.
  • This hypothesis is supported by various experimental models, including cell cultures, invertebrates, and mammals.

Purpose of the Study:

  • To critically review the evidence that supports the free radical theory of aging.
  • To examine the evidence that conflicts with the free radical theory of aging.
  • To explore the relationship between mitochondrial metabolism, oxidant production, and the aging process.

Main Methods:

  • Literature review of studies investigating the free radical theory of aging.
  • Analysis of evidence from cell culture, invertebrate, and mammalian models.
  • Examination of research linking mitochondrial function and aging.

Main Results:

  • Evidence exists that supports the free radical theory of aging.
  • Evidence also exists that conflicts with the free radical theory of aging.
  • A significant connection is observed between mitochondrial metabolism, the formation of oxidants, and the biological mechanisms of aging.

Conclusions:

  • The free radical theory of aging remains a significant hypothesis, but requires further investigation.
  • Mitochondrial metabolism and oxidant formation are increasingly recognized as critical factors in aging.
  • A comprehensive understanding of aging necessitates considering multiple interconnected biological processes.